The Division of Pediatric Hematology-Oncology at the University of Michigan Health System collaborates in all open studies of the Children's Cancer Group, with the goal of improving the care and survival of children with cancer. The Division is a member of the University of Michigan Comprehensive Cancer Center, an N.C.I.-designated comprehensive cancer center, one of two in the State of Michigan, and has eight full-time clinical investigators with faculty appointments at the University of Michigan Medical School, as well as an approved fellowship program in pediatric hematology-oncology with two fellows in training for each of three years. In addition, participation if CCG research activities is enhanced through collaboration with five affiliate institutions located in the more populous regions of Michigan (two in the Detroit area, one in Grand Rapids, one in East Lansing, and one in Kalamazoo). For the University of Michigan CCG Network, patient registrations on therapeutic studies numbered 121 for the 12-month period from June 1, 1996 through May 31, 1997, while entries on biology and non-therapeutic studies numbered 81. During the same time period, patients in follow-up at institutions of the University of Michigan CCG Network numbered 791. During a recent 18-month period (12/1/95 through 5/31/97), The University of Michigan CCG Network was ranked fourth among 35 institutions for therapeutic study entries, fourth for biology study entries, fifth for entries on other studies, fourth for total patients on study in follow-up, and fourth for overall data quality. The University of Michigan is one of 17 CCG institutions approved for participation in phase I studies and is a CCG-approved bone marrow transplant center. A total of 22 multidisciplinary investigators have appointments to scientific, discipline, and study committees and to strategy groups. In the future, these investigators at the University of Michigan will continue to contribute to CCG therapeutic, epidemiology, and biology research for a wide range of malignant diseases. Additional contributions can be expected in the areas of phase I clinical trials and bone marrow transplantation. Finally, investigators in Pediatric Hematology-Oncology at the University are currently making contributions to the molecular biology of leukemia, neuroblastoma and brain tumors; these studies will eventually be expanded to clinical trials in CCG in order to evaluate the clinical relevance and the prognostic importance of the findings.